The RSPCA is calling on retailers to stop selling cheap meat from chickens reared in poor conditions, saying shoppers should be prepared to pay more to ensure they are bred in a better environment.

The charity wants supermarkets to sell only "higher welfare chicken" - free-range, organic or produced to its own Freedom Food standards - by 2010.

It says the overwhelming majority of the 855m chickens reared for their meat in the UK every year are kept in cramped, dimly lit spaces, and has created an online petition for consumers to put pressure on retailers - supportchickennow.co.uk.

Millions of shoppers already shun eggs from battery farms, with almost 38% of eggs sold in the UK now coming from non-caged hens. However, only about 5% of chickens reared in the UK for meat are kept in higher welfare conditions.

The RSPCA's campaign, launched today with full-page adverts in the form of an open letter to retailers in four national newspapers, including the Guardian, is timed to coincide with a short season of Channel 4 programmes, featuring Jamie Oliver and Hugh Fearnley-Whittingstall, focusing on chicken farming.

Fearnley-Whittingstall's Chicken Run, a three-part series, will also challenge the major chains to change their ways. The River Cottage chef set up his own intensive-rearing chicken farm near his home in Axminster, Devon, to show "what happens to chickens that are sold for less than the price of a pint of beer".

Dr Marc Cooper, an RSPCA farm animal scientist, said: "If people knew how the average chicken was treated before it ended up as their Sunday roast, they would probably be disgusted. Some supermarkets are selling chicken meat for as little as £2 per kilo - this can be less than it costs to produce the bird." Such low prices meant farmers did not get enough money to enable or encourage them to rear the birds in acceptable conditions, he added.

"Everyone has a responsibility to ensure chickens are reared to high standards. We are asking supermarkets to stop selling standard chicken and shoppers to stop buying it. We are asking shoppers to demonstrate to supermarkets that there is a demand for higher welfare chicken by signing our petition and by showing they are willing to pay a little bit more money for a bird that's had a better life."

The RSPCA says about 95% of the chickens bred in the UK every year are reared to the industry's standards, which allocate less space than a sheet of A4 paper to each bird in a shed. Near-constant dim light discourages activity to maximise their growth and they are given only a few hours of complete darkness each day in which to rest properly.